Imidazole derivatives have been conventionally known to show pharmacological actions such as inhibitory action on the synthesis of thromboxane A.sub.2, and thereby-induced blood platelet aggregation-inhibitory action and vasodilative action, and also known to be useful for the prophylaxis and treatment of the circulatory organ disorders, such as thrombosis, cerebral apoplexy, and so on, as well as allergy. Yet, these derivatives have been studied in terms of pharmacological action for relatively a short time, and there is a great expectation for the application of the derivatives as pharmaceuticals and toward the creation of new drugs.
At present, a compound of the formula (V) ##STR3## is being used at the clinical situations as an imidazole derivative preparation for the prophylaxis and treatment of cerebrovascular spasm. Moreover, the effectiveness of the imidazole derivative against bronchial asthma has been recently confirmed, and its novel use as an agent for treating asthma has received increasing attention.
Accordingly, an object of the present invention is to provide a novel, low-toxic imidazole derivative or a pharmacologically acceptable salt thereof which exhibits extremely superior pharmacological activities, namely, pharmacological actions such as inhibitory action on the synthesis of thromboxane A.sub.2 ; thereby-induced blood platelet aggregation-inhibitory action and vasodilative action; antihistaminic action; and inhibitory action on respiratory tract contraction caused by histamine or leukotriene.
Another object of the present invention is to provide an agent for the prophylaxis and treatment of the diseases induced by thromboxane A.sub.2 or histamine, namely, an agent for the prophylaxis and treatment of thrombosis, cerebral apoplexy, ischemic cerebral circulatory disorders angina pectoris myocardial infarction, nephritis, allergy, asthma, and so on.
Still another object of the present invention is to provide a compound useful as an intermediate for the production of said imidazole derivatives.